# include <Servo.h>

Servo my ;
int pos=0;
void setup() {
  // put your setup code here, to run once:
my.attach(9);

}

void loop() {
  // put your main code here, to run repeatedly:
  for (pos=0;pos<=180;pos++){
    my.write(pos);
    delay(15);
  }
  for (pos=180;pos>=0;pos--){
    my.write(pos);
    delay(15);
  }

}